This invention relates to an anaerobic treatment method for rapidly and effeciently treating a fluid containing anaerobic digestible nutrients and primarily organic substrates.
The most pertinent art known to the Applicants at the time of filing this application is embodied in the following United States Patents:
______________________________________ 2,029,702 3,941,691 2,899,385 3,943,055 3,105,014 3,994,780 3,598,726 4,043,936 3,724,542 ______________________________________
Heretofore most anaerobic treatment processes have been carried out in either relatively large holding tanks, lagoons or in packed columns. In either case, an anaerobic biomass is generally immersed within a fluid material that is being treated. These prior art devices thus operate under flooded conditions so that the microorganisms are forced to both feed and exhaust process gases while underwater. As a consequence, the microorganisms become highly saturated with process gases which are either inhibitory or toxic to the microorganisms and thus experience a relatively high resistance when they attempt to function in this environment. A natural resistance to efficient metabolism and substrate utilization is therefore inherently present in all flooded aerobic treatment systems which therefore inherently require relatively long mean cell detention times relative to anaerobic treatment. Even with retention periods of between 30 and 50 days the quality of the effluent is sometimes poor. Similarly, because of the typically low growth rate for most anaerobic microorganisms large volume holding or treatment tanks are required which necessitate large capital expenditures for both land and equipment. Oftentimes, because of the complexity of the equipment involved, operational difficulties are encountered which compound the existing time and money problems normally associated with many anaerobic processes.